It is well known in the electronic industry to provide substrate is, presumably in the form of printed circuit boards, which carry upon one or both sides, electronic components which provide various electronic functions. It is also known that electronic components generate heat and certain components also emit electromagnetic radiation which interferes with the operation of other components on a printed circuit board or with other electronic devices not mounted upon the board. A board mounted electronic component may be in the form of an integrated circuit or a chip. The tendency in modern design is for integrated circuits or chips to become smaller and faster in operation. A problem which exists with faster operation of smaller circuits is that they tend to increase in temperature and may overheat to such a degree that permanent damage may result unless steps are taken to avoid such situations.
In this case, heat removal becomes a prime necessity. However, heat removal considerations may be contradictory to the considerations necessary for overcoming electromagnetic emission problems. This is because for the avoidance of EMI emissions, a surrounding shield is normally necessary for an integrated circuit and this detracts from the removal of heat because such a shield tends to act as a heat insulator.
Generally, heat sinks are mounted to an outer surface of an integrated circuit package to facilitate the removal of heat from the integrated circuit contained therein. Most heat sinks are thermally conductive and have a plurality of fins to provide a large surface area, which allows heat to be more efficiently dissipated by natural or forced air flow. Generally, heat sinks transfer heat from the integrated circuit to the air inside the computer chassis by means of convection. This increases the overall temperature within the computer chassis. For chips with greater heat dissipation needs, fans are also used in conjunction with heat sinks to increase the rate of heat dissipation. Fans may be arranged to direct heat from inside the computer chassis towards holes in the computer chassis, thus moving hot air to the outside of the computer chassis. These fans are generally very noisy, consume power and take-up space inside the electronic chassis.
There is a need for a heat sink device that can more efficiently dissipate heat to the outside of the computer chassis, while at the same time reducing EMI emissions from the integrated circuit to the chassis. It would also be advantageous to be able to dissipate heat without the use of fans.